sustainable software developmt

8/8/2019 Sustainable Software Developmt

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Sam HwangSam Hwang

2010 Mar2010 Mar


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Project Stresses

User Requirements

External Dependencies

Competition

Disruptive Technologies

Disruptive Business Models

Cost Management

Project Controls

Collaboration

Methodology

ExpertiseDecision Making

Leadership

Culture

Simplicity


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A User need and vision so it is clear what is being built

Rapid refinement to adapt to change

A Close relationship with users so they can providetimely feedback

Continual learning to refine the product so it best meetsuser needs while avoiding unnecessary features


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Continual Refinement of the product & project practices

A Working product at all times

A Continual investment in & Emphasis on design

Valuing Defect Prevention over defect detection


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Features

WorkingProduct

DefectPrevention

ContinualRefinement

Bug-fixing

DesignEmphasis


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WorkingProduct

Virtually Shippable

Ultimate goal

Flexibility Agility


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No Broken Windows Be Uncompromising about Defects Barely sufficient Documentation Continuous Integration Nightly Builds Prototyping Don't Neglect Performance

Zero Tolerance for Money and Resource Leaks Coding Standards and Guidelines Adopt Standards (Concentrate on Your Value-Add)

Internationalize from Day One Isolate Platform Dependencies


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Numberof DefectsFound

Numberof DefectsFound

Developers QA Customers Developers QA Customers

Defect Defection Defect Prevention

Code then Fix Manual Testing Low-value manual testing

Finding defects Automated Test High-value manual testing


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Ruthless Testing

Use Available Tools

Pair Programming & Code Reviews

Lightweight Root-Cause Analysis


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Software must be designed to support and enhance changeabilitychangeability

WellWell-- designed software is useful and easy to:designed software is useful and easy to:

UseUse

MaintainMaintain

ExtendExtend

Understand.Understand.

The elements of design in sustainable software development are:

Working softwareWorking software

The process of doing the designThe process of doing the design Collaboration and faceCollaboration and face--toto--face communicationface communication

Simple designSimple design


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Design vision Guiding Principles Simple Design

Refactoring Design Pattern Frequent Rapid Design Meetings Commitment to Rearchitecture Design for Reuse


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Teams need a way to balance short-term requirements andlong-term needs: to ship their product as soon as they can whileaccepting, anticipating, and even welcoming change

The core agile software development practice of iterativedevelopment encourages continual refinement

In agile development, teams work from a simple and clear

vision and deal with change through frequent iterations; the goalof each iteration is to deliver something useful to customers

The main advantage of agile methods is that they help teams

manage uncertainty and change early and throughout theproject


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Iterative Development

Release Planning

Daily Standup Meetings

Retrospectives

Coaching & Team Development

Make Key Metrics Visible


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Organizations are complex simply : the mix of different people

Software people :

Come from many backgrounds Tend to be introverts Don't like being told how to work

Many organization do not pay attention to key people issues

Professional development and leadership Focus on projects, schedules, and results

Software education lacks standards and a poor understanding ofwhat the basic are


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Culture Factors:

Leadership Sense of urgency

Executive support

Culture Enablers:

Persistence Training

Continuous wins Positive reinforcement of desired behaviors Communication


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Background Software development is a complex undertaking The method : code-then fix or waterfall method

Unsustainable Development Too many projects cant cope with the complexity ofthe software development taking

The teams are largely only able to respond tochanges in their ecosystem The most effort goes toward adding features and

fixing bugs These projects respond to complexity with complexsolutions that are unreliable(buggy), brittle(break easily),and unable to support future change


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Sustainable Development

Teams are able to be proactive about changes intheir ecosystem Requires acknowledging the need for change

It means that adapting a different mindset and beinguncompromising

The Principle of sustainable Development Having a working product every day Defect prevention Design emphasis Continual refinement


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Having a working product every day

Even if it is not functionally complete, gives teams flexibility allows teams to be much more responsive to

changes in their ecosystem

Defect prevention

A change in mindset for virtually all teams Central to defect prevention: the practice of ruthless testing computers are relied upon to do the repetitiveand boring testing tasks that people do today


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Design emphasis

Good design is required to ensure that the period isdesigned to promote future maintainability andmodifiability

Simple design, refactoring and design patterns allplay important role in design Every project and team has to find the right balance

between iterative design and up-front design

Continual refinement Applies to how the project is planned and trackedthrough iterative development Team can continually enhance its developmentprocesses and collaboration

sustainable software developmt

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